关于出油阀校正的若干问题的研究

本文对柴油机喷油过程中的出油阀校正问题进行了多方案的试验研究,探讨了出油阀校正的机理和出油阀校正对喷油过程的影响。指出了采用出油阀校正的限制因素是柴油机的低速烟度和机械加工工艺水平,采用合适的出油阀结构型式可放宽对机械加工精度的要求,使成批生产成为可能。     

Obtaining transgenic rice resistant to rice fungal blast disease by controlled cell death strategy

The strategy of the two-component system,composed of Barnase and Barstar which encode RNase and a specific inhibitor to the RNase respectively, is adopted to obtain transgenic rice resistant to rice fungal blast disease. In this study, two chimeric promoters, induced by rice blast fungus pathogen (Magnaporthe grisea), are fused with Barnase respectively to construct two plant expression vectors, pWBNBS and pPBNBS together with the Barstar driven by CaMV 35S promoter. The resistance of the transgenic rice lines to rice blast fungus disease and rice blight disease are evaluated. The results show that (1) the expression of Barnase is induced in rice leaves when inoculated with the spores of Magnaporthe grisea; (2) the induced expression level of Barnase surpasses the level of Barstar, which elicits a similar hypersensitive response (HR) in the leaves, and the transgenic plant shows high resistance to the rice fungal blast disease; and (3) transgenic rice plants also show obvious resistance to rice bacterial blight disease. Taken together, these results suggest that the transgenic rice plants harboring this two-component system acquire relatively broad spectrum resistance against pathogens, especially high resistance to rice fungal pathogen.     

碳化混凝土再碱化施工规程

碳化混凝土再碱化技术应用电化学、电渗原理、扩散等作用,在混凝土中的钢筋和混凝土外围碳酸钠溶液之间施加一个电场,在直流电的作用下,恢复钢筋周围混凝土的碱性环境,使得钢筋再钝化,达到防止钢筋锈蚀的目的。在再碱化已有的研究成果基础上,为了推进电化学再碱化技术在实际工程中的应用,结合理论分析,提出施工工艺,编制了碳化混凝土再碱化的施工规程。     

机动车排放模型的应用及其适用性比较

运用模型估算城市机动车排放因子及排放总量,是机动车污染控制研究的一个重要方向。目前,在模型使用方面,国内主要借用MOBILE等国外较为成熟的模型,这在我国排放因子计算方面缺乏数据积累、基础研究薄弱情况下不失为一种选择。然而,这些模型一般根据不同的需要开发,在数据积累等方面具有较强的地域性,难免会与国内实际情况不符。国内现有研究更多集中于对利用模型得到的排放因子进行分析,对模型适用性的研究鲜有涉及。本文从MOBILE,IVE,EMFAC,CMEM,COPERT模型在国内应用的实际情况出发,从模型类型,地域性,数据库的完整性、模型的可移植性和参数可获性这几个方面,比较了这几个有代表性的机动车排放模型在国内的适用程度,指出了在不同地区情况和不同阶段,模型不同的适用范围。     

基于CAS理论的循环经济适宜性评价与实证研究

基于物质存在闭环流动这一循环经济的重要特征,借助复杂适应系统理论的多主体建模工具,设计了循环经济的Swarm仿真模型。模拟结果表明采用了循环经济模式的“recycle世界"中,生产-消费个体不再出现周期性变化规律,而是在仿真时间150个步长左右达到动态平衡,同时仿真世界对生产-消费个体的最高承载能力由0.06上升到0.20;而维持系统稳定性必须保证概念模型中从“消费者”到“生产者”的反馈有效运行,对应到现实世界,即影响区域发展循环经济的适宜性的主要因素表现在技术、产业、市场、社会4个方面。以深圳市宝安区这一经济快速发展的区域为例建立了一套基于上述4个因素的半定量化的评价指标,认为该区现阶段适宜于发展弱关联型循环经济体系。     

环境影响评价中公众行为选择概念模型

参与和不参与是公众个体在环境影响评价参与契机下的两种行为选择,作者从理性经济人假设出发,分析出环境偏好、责任意识、制度供给与政府行为规范、舆论情景等构成了理性公众个体行为选择模型变量的主因子,它们决定着参与或不参与成本,并影响着公众个体对参与效力的预期。通过对可能存在的公众行为选择的无差异曲线,分析公众行为选择倾向,潜在的积极参与个体,以及改变其选择倾向的可能性。     

Hydrous manganese dioxide adsorbing humic acid： controlling trihalomethane formation

Effectiveness of hydrous manganese dioxide (δMnO2) adsorbing humic acid under different conditions and its subsequent effects on trihalomethane (THMs) formation have been studied. Humicacid removal increases with higher pH and residual TOC decreases from 3.63 mg/L to 1.68 mg/L with pH increasing from 5.5 to 8.5 at 3.0 mg/L δMnO2; δMnO2 exhibits good potential of removing humic acid and the adsorbing potential as high as 1 mg TOC/mg δMnO2 is achieved; the fractional reduction of humic acid with higher molecular weight is about 30% higher than that with lower molecular weight. δMnO2 adsorption obviously reduces subsequent THMs formation; more significant THMs formation reduction is observed for humic acid with higher molecular weight. δMnO2 adsorption is an important factor that contributes to humic acid removal and THMs formation reduction in permanganate pre-oxidation process.     

新疆伊犁河谷新垦荒地土壤粒度特征

在新疆伊犁河谷察布查尔县农业示范区采集17个土壤剖面合计119个样品,进行土壤粒度分析和综合对比研究.结果表明:1)不同土地类型土壤砂粒(＞50μm)、粉砂(2～50μm)和粘粒(＜2μm)含量差异较明显.多数耕作土壤样本的粉砂含量低于天然荒地,而砂粒含量要高于荒地土壤.2)各种类型土壤剖面粘粒和砂粒组分含量的变异均大于粉砂含量的变化,其中耕作土壤各粒级含量的变异系数要大于荒地土壤,各类土壤表层和下层粒度变异系数也不同.3)不同土地类型土壤的粒度参数存在差异.耕作土壤的平均粒径小于荒地土壤,且前者的分选性要比后者差,这与不同人为耕作方式对土壤粒度组成的扰动密切相关.     

Expression and inhibitory activity analysis of a 25-kD Bowman-Birk protease inhibitor in rice

Bowman-Birk protease inhibitors (BBI), belonging to serine protease inhibitors, are well-studied storage and defense proteins widely existing in both dicoty- ledonous and monocotyledonous plants[1―3]. In dicoty- ledonous plants, the BBIs are about 8-kD p…     

过氧化物模拟酶氯化血红素含量的测定

以氯化血红素(Hemin)作为过氧化物模拟酶,4-氨基安替比林(4-aminoantipyrine,4-AAP)和苯酚(phenol)为氢供体底物,通过Hemin催化活化H2O2氧化底物偶联显色反应,建立了测定Hemin含量的分析方法.实验表明在pH为10.0条件下,Hemin在0~1.28×10-6mol/L线性范围内符合朗伯-比尔定律,测定Hemin表观摩尔吸光系数为4.05×105L.mol-1.cm-1,以加入回收法试验Hemin的含量测定,结果满意.